Steam boiler



Nov. l2, 1929. H. B. SMITH STEAM BOILEH Filed Jan. 21, 192e Patented Nov. 12, 1929 UNITED STATES PATENT OFFICE HERMAN B. SMITH, Fy PLAINFIELD, NEW JERSEY, ASSIGNOR .TO THE BABCOCK t WILCOX COMPANY, OF BAYONNE, `NEW JERSEY, A CORPORATION 0F NEW JERSEY STEAM BOILER Application led January 21, 1926. Serial No. 82,696.

My present invention relates to steam'boilers, and particularly to boilers adapted vfor use with waste gases which are heavily dust laden, and will be best understood from the s VJfollowing description and the annexed drawing which shows a longitudinal sectional elevation of an illustrative form embodying my invention.

In the illustrative embodiment, there are 1o three upper steam and water drums 10, 11 and 12 and two lower water drums 13 and 14. The upper steam and water drums are spaced apart and are connected by steam eirculators 15, 16 and water eirculators 17,18. The lower drums 13 and 14 may be connected by a. row

of circulators 14'.

The lower water drum 13 is positioned out of vertical alinement with either the front drum or the middle drum 11 and beneath the 2g space between these two upper drums. Similarly, the lower drum 14 is positioned out of vertical alinement with either the middle drum l1 or the rear drum 12 and beneath the space between these two drums.

A bank of tubes 19 have their upper ends connected to the drum 10 in the usual manner, so as to enter radially therein, the tubes 19 being substantially straight and vertical I'or the major portion of their length, being bent at their lower ends and entered radially into the drum 13.

A row 19 of the front bank of tubes 19 is separated from the main bank to provide a superheater space in which is positioned a superheater having U-tubes 20 extending horizontally into this space, the U-tubes having their legs connected respectively with an inlet header 21 and an outlet header 22 preferably located outside of the side wall of the boiler setting. A pipe 23 connects the rear steam and water drum with the inlet header 21.

The middlesteam and water drum 11 is connected with the front lower drum 13 by a bank of tubes 24, these tubes being straight and vertical for the major portion of their length with their ends bent to enter each of the drums radially.

The rear steam and water drum 12 is con'` 50 nected to the rear lower drum 14 by a bank of tubes 25, these tubes also beingstraight and Vertical for the major portion of their length with their ends bent to enter the respective drums radially. A row 25 of the rear bank is spaced from themain bank.

The front wall 26 of the boiler setting extends vertically along the straight portions of the tubes 19 and a baille 27 is connected to the tubes 19', this balile 27 and the front wall 26 forming a vertical flue through which eX- tends the front Abank of tubes 19. The baille 27'is spaced from the drum 10, so that gases flowing upward in this vertical flue, can pass over the baille between the tubes 19 into the bank of tubes 24, this bank being positioned in a vertical flue formed by the baille 27 and a baille 28 supported on the tubes 25. The baille 28 does not extend tor the lower drum 14, so that the gases flowing downward in this middle flue or pass will flow into the rear bank of tubes 25 beneath the lower end of the baille 28 between the tubes 25. At the rear of the bank 25 is a wall 29 forming with the baille 28, a flue in which is positioned the tubes 25. The gases flowing upward in this flue or ass are directed over the top of the wall 29 into an economizer 30, over the tubes of which the gases flow downward to the gas outlet 31. The economizer 30 is made up of a plurality of vertical headers on each side of the setting, these headers being nippled end to end and the lowermost vertical header being connected to a horizontal header 32 through which the feed water enters to flow upward in each of the vertical headers, passing back and forth across the flue through the economizer tubes until the upper header 33 is reached, from which the water passes through any appropriate piping into the boiler, preferably into the rear steam and water drum 12.

The boiler .described above is particularly adapted for use with gases from industrial furnaces, such as cement kilns and the like, and I have illustrated an arrangement by which waste gases from cement kilns may be supplied to the boiler. In the drawing, 34 represents such an external source of waste gases, for example, the lend of a cement kiln, of which there may be as many as desired, delivering gases to a ,common line 35, from which flue the gases pass through the duct 36 controlled by a damper 37 into a passage 38 which is directly below the vertical flue ormed by the front wall 26 and the baliie. Consequently the gases flow vertically upward into this vertical iiue, past the drum 13, entering the bank of tubes 19 through the lower bent portions thereot.4 The gases, after flowing over the tubes 19, pass into the middle and rear passes as described above, and iinally through the economizer to the gas outlet 31. Auxiliary baliles 39 are provided in the respective passes to direct the gases into the respective banks of tubes, these auxiliary battles preferably being made of metal and being inclined away from the tubes toward the wall or batlie with which they cooperate. lllhe baile 39 between the first and second passes may be made horizontal, as shown.

A bridge wall 40 is vpositioned beneath the drum 13 and any suitable gas seal 41 is provided between the drum 13 and the wall 40. Beneath lthe front vertical Hue and beneath the gas inlet 38 is a dust hopper 42 and beneath the middle and rear passes of the boiler is a dust hopper 43. A dust hopper 44 may also be provided beneath the economizer.

It will be understood that the boiler which I have provided is arranged so that the dust settling from the heatin gases will nd little or no lodgment on the eating surfaces, and particularly on the lower drums 13 and 14. For instance, in the first pass, as the dust settles out of the gases, it will fall downward through the front pass or iue through the lower bent portions of the tubes 19 into the hopper 42, which would not be the case it the drum 13 were located beneath the drum'lO, so that the tubes 19 would not be bent sharply to the right in the igure as is done inA my preferred form. Similarly, the drums 13 and 14 are positioned with respect to the middle and rear passes, so that the dust carried downward in the middle pass and falling out of the gases in the rear pass, can drop into the hopper 43 without finding any substantial lodgment on the drums 13 and 14.

By sloping the auxiliary baiiies 39, as shown, any dust collecting thereon will slide down into the respective passes and from thence into the hoppers below. 1t will also be noted that in my arrangement, the boiler can be, and preferably will be supported from the upper steam and water drums, leaving the lower drums 13 and 14 free to move in accordance with the expansion and contraction of the several water tubes, and yet only one gas seal is needed to prevent short-circuiting of the gases by reason of such movement. Furthermore, by forming the wall 29 of plates, the economizer can be incorporated in a single setting with the boiler and, indeed, can be vsuspended with the' boiler. By positioning the superheater in the manner shown, the superheater headers are removed from the passes so that dust cannot accumulate thereon.

It will also be noted that I haveshown five rows of tubes in the front bank, seven rows in the middle bank and seven rows in the rear bank, the tubes 19 and 25 being disregarded in the foregoing statement. By this arrangement of tubes the total heat absorption in the second and third banks is greater than if the number were the same as in the iirst bank; that is, as the gases progressively are lowered in temperature the amount ofsurface furnished for the absorption o heat from such gases is progressively increased.

I claim:

1. A steam boiler having a vertical ilue, a steam and water drum at the top of said flue, a water drum at the bottom of said flue and at one side thereof, a bank of tubes connected to the upper drum and extending vertically in said iiue for the major portion of their length and having their lower ends bent and connected to said lower drum, an external source of hot gases, and a gas inlet connecting said source to the bottom of said flue, and means to direct the hotgases from the inlet into the bank from beneath the bent port-ions of the tubes.

2. A steam boiler having a vertical flue, a steam and water drum at the top of said flue, a water drum at the bottom of said iue and at one side thereof, a bank of tubes connected to the upper drum and extending vertically in said flue for the major portion of their length and having their lower ends bent and connected to said lower drum, a hot gas inlet connected to the bottom of said fine to direct the hot gases into the bank from beneath the bent portions of the tubes, at least one of the rows of tubes in said bank being separated from the main bank to form a superheater chamber, and a superheater in said chamber.

3. A steam boiler having a vertical flue, a

steam and water drum at the top of said flue,

a water drum at the bottom of said iue and at one side thereof, a bank of tubes connected to the upper drum and extending vertically in said ue for the major portion of their length and having their lower ends bent and connected to said lower drum, a hot gas inlet connected to the bottom of said flue to direct the hot gases into the bank from beneath the bent portions of the tubes, at leastone of the rows of tubes in said bank being separated from the main bank to'form a superheater chamber, and a superheater in said chamber, said superheater having vertically disposed inlet and outlet headers and tubes extending across said iu'e and connecting said headers.

4. A steam boiler having two upper steam and water drums spaced apart and a lower water drum positioned beneath the space between the upper drums, a bank of tubes connecting each upper drum and the lower drum, a boiler wall and a baHle between the banks defining a vertical Hue with the front bank of tubes in said flue, the tubes in said front bank being straight and vertical for the major portion of their length and bentat their lower ends, an external source of hot gases and a gas inlet connecting said source to the bottom of said Hue, and means to direct the hot gases from the inlet into the bank from beneath the bent portions of the tubes, the top of said baHle being spaced from the drums to permit the gases to How from the first bank into the second bank.

5. A steam boiler havin a vertical Hue, a

steam and water drum att e top of said HueI a water drum at the bottom of said Hue and at one side thereof, a bank of tubes connected to the upper drum and extending vertically in said Hue for the major portion of their length and having their lower ends bent and connected to said lower drum, a hot gas inlet connected to the bottom of said Hue to direct the hot gases into the banky from beneath the bent portions of the tubes, and auxiliary 'bailles between the outside rows of tubes in said bank and the walls of the Hue and inclined upward from the tubes to the walls of the Hue.

6. A steam boiler havin a vertical Hue, a steam and water drum at t e top of said Hue, a water drum at the bottom of said Hue and at one side thereof, a bank of tubes connected to the upper drum and extending vertically in said Hue for the major portion of their length and having their lower ends bent and connected to said lower drum, a hot gas inlet connected to the bottom of said Hue to direct the hot gases into the bank from beneath the bent portions of the tubes, and a dust hopper belneath said vertical Hue and said hot gas in et.

7. A steam boiler having three upper steam and water drums spaced apart and connected by circulators, two lower water drums connected by circulators and spaced apart with one of said lower drums positioned beneath the space between the front and the middle upper drums and the other lower drum positioned beneath the space between tlie middle upper drum and the rear upper drum, banks of tubes connecting the front and middle upper drums to the front lower drum, a bank of tubes connecting the rear upper druin and the rear lower drum, a boiler setting and baHles between the banks to form three vertical Hues each with a bank of tubes therein, a hot gas inlet connected to the bottom of the Hue containing the front bank of tubes and the baHles being arranged to permit the gases to How from the to of the front Hue into he middle Hue, and om the bottom of the middle Hue into the rear Hue, the major portion ofthe tubes in each bank being straight and vertical with their lower ends bent to enter the respective lower i drums and each lower drum being positioned at one 'side of its res ective vertical Hue.

8. A steam boiler avin a vertical Hue, a steam and water drumat te top of said Hue, a water drum at the bottom of said Hue and at one side thereof, a bank of tubes connected l Hected.

HERMAN B. SMITH. 

